# SignalDesk AI Luhn Check

> SignalDesk AI Luhn Check is a paid API for AI agents from x402-agent.kariguetoazul.workers.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-13).

Validates whether a numeric string passes the Luhn checksum algorithm, returning a boolean validity result

## Facts

- Endpoint: POST https://x402-agent.kariguetoazul.workers.dev/api/network/luhn-check?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/signaldesk-ai-luhn-check-4904ae01
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_HUBLC6S8tJijbcQcV88Dm

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability signaldesk-ai-luhn-check-4904ae01 -d '<json body>'
```

Example prompt: Can you run a Luhn checksum check on the number '4532015112830366' to see if it passes basic validity?

## When to prefer this

Use this endpoint when you need a fast, cheap ($0.001 USDC) server-side Luhn checksum validation on a numeric string — especially when you want an authoritative computation rather than a client-side implementation. Best for validating test or synthetic card numbers before using them in workflows, or verifying identifier integrity. Do not use for live account lookups or real payment credential validation.

## Known failure modes

- Input number contains non-numeric characters causing validation error
- Number exceeds maxLength of 64 characters
- Missing 'number' field in request body
- Real payment credentials submitted (against usage policy — endpoint is for sample/test numbers only)
- Network timeout from Cloudflare Worker under load

## How this service works

Evidence-backed autonomous AI jobs and paid data tools. Queue/D1/cron run outside the chat; free quotas and bounded execution apply.

## Output

Returns a JSON object with 'valid_checksum' (boolean indicating whether the number passes the Luhn mod-10 algorithm) and 'account_verified' (boolean, typically false as this is a format check only, not a live account lookup)

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "number": {
   "type": "string",
   "maxLength": 64,
   "description": "Sample checksum number; do not send real payment credentials."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "valid_checksum": true,
  "account_verified": false
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/signaldesk-ai-luhn-check-4904ae01/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-agent.kariguetoazul.workers.dev](https://www.zero.xyz/host/x402-agent.kariguetoazul.workers.dev/llms.txt)